package com.zmzncs.lmtc.common.util;

import org.springframework.util.DigestUtils;

import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class MD5Util {

    public static void main(String[] args) {
        System.out.println(generatePassword("admin"));

        System.out.println(md5("a4ed2cfe01100ca92ce4ddc0634c72ba" + "630242567"));
//        System.out.println(generatePassword("a4ed2cfe01100ca92ce4ddc0634c72ba" + "630242567"));
    }

    /**
     * md5加密
     */
    public static String md5(String str){

        return DigestUtils.md5DigestAsHex(str.getBytes());
    }

    /**
     * 生成密码
     */
    public static String generatePassword(String passwork){
        return DigestUtils.md5DigestAsHex(("中萌智能城市" + passwork).getBytes());
//        try {
//            // 生成一个MD5加密计算摘要
//            MessageDigest messageDigest = MessageDigest.getInstance("MD5");
//            // 计算md5函数
//            messageDigest.update(("中萌智能城市" + passwork).getBytes());
//            // digest()最后确定返回md5 hash值，返回值为8为字符串。因为md5 hash值是16位的hex值，实际上就是8位的字符
//            // BigInteger函数则将8位的字符串转换成16位hex值，用字符串来表示；得到字符串形式的hash值
//            return new BigInteger(1, messageDigest.digest()).toString(16);
//        } catch (Exception e) {
//            e.printStackTrace();
//            return null;
//        }
    }

    private static String byteArrayToHexString(byte b[]) {
        StringBuffer resultSb = new StringBuffer();
        for (int i = 0; i < b.length; i++)
            resultSb.append(byteToHexString(b[i]));
        return resultSb.toString();
    }

    public static String MD5Encode(String origin, String charsetname) {
        String resultString = null;
        try {
            resultString = new String(origin);
            MessageDigest md = MessageDigest.getInstance("MD5");
            if (charsetname == null || "".equals(charsetname))
                resultString = byteArrayToHexString(md.digest(resultString.getBytes()));
            else
                resultString = byteArrayToHexString(md.digest(resultString.getBytes(charsetname)));
        } catch (Exception e) {
            e.printStackTrace();
        }

        return resultString;
    }

    //32位大写toUpperCase()
    public static String md5ToUpperCase(String str) {
        return DigestUtils.md5DigestAsHex(str.getBytes()).toUpperCase();
    }

    private static String byteToHexString(byte b) {
        int n = b;
        if (n < 0)
            n += 256;
        int d1 = n / 16;
        int d2 = n % 16;
        return hexDigits[d1] + hexDigits[d2];
    }

    public static String convertMD5(String inStr) {
        char[] a = inStr.toCharArray();
        for (int i = 0; i < a.length; i++) {
            a[i] = (char) (a[i] ^ 't');
        }
        String s = new String(a);
        return s;
    }

    private static final String hexDigits[] = {"0", "1", "2", "3", "4", "5",
            "6", "7", "8", "9", "a", "b", "c", "d", "e", "f"};

}